We have found 12 plants that meet your criteria.

Bugbane (syn. Cimicifuga) ‘Actaea simplex Atropurpurea Group’ A late-flowering perennial for shade £8.99 Buy
Price Pruned
Bugbane (syn. Cimicifuga) ‘Actaea simplex Brunette’ Tall, dramatic flower spikes in early autumn NOW £12.99 Buy
Cow Parsley ‘Anthriscus sylvestris Ravenswing’ Lacy purple foliage with a sprinkling of white flowers £6.99 Buy
Aster ‘Aster lateriflorus Lady in Black’ Masses of tiny, pink-tinged daisies £5.99 Buy
Price Pruned
Ginger Lily ‘Hedychium greenii’ A more compact form with red flowers NOW £6.99 Buy
New Zealand Flax ‘Phormium Platt's Black’ Dramatic, almost black, strappy foliage £13.99 Buy
Rodgersia ‘Rodgersia pinnata Chocolate Wing’ Rich chocolate brown leaves are produced in the spring. £5.99 Buy
Price Pruned
Barberry ‘Berberis thunbergii Helmond Pillar’ An upright shrub with purple leaves NOW £5.99 Buy
Price Pruned
Cardinal Flower ‘Lobelia cardinalis Queen Victoria’ Bright red flowers and maroon foliage NOW £5.49 Buy
New Zealand Flax ‘Phormium Bronze Baby’ Compact variety with purple-bronze leaves £13.99 Buy
Purple Sage ‘Salvia officinalis Purpurascens’ Attractive red-purple young leaves £4.99 Buy
Black Elder (syn. Black... ‘Sambucus nigra Eva’ A striking plant with dramatic almost black,... £8.99 Buy